The instant invention reflects an ongoing evolution of structure, disclosed in U.S. application Ser. No. 07/419,095 filed Oct. 10, 1989, to the instant inventor.
The prior art is relatively rich in attempts at providing construction blocks for children which challenge the child's imagination yet are not so complex as to frustrate the child in his creative endeavors. Not surprisingly, many known patents can be grouped into the above noted objection categories as being either too simple or too complex.
The following patents reflect the state of the art of which applicant is aware and is included herewith to discharge applicant's acknowledged duty to disclose relevant prior art. It is stipulated, however, that none of these references teach singly nor render obvious when considered in any conceivable combination the nexus of the instant invention as disclosed in greater detail hereinafter and as particularly claimed.
______________________________________ INVENTOR PATENT NO. ISSUE DATE ______________________________________ Bersani FR2534-481-A 4/20/84 Inskip EP-109-181-A 5/23/84 Playcraft Toys, Inc. BR1,167,678 10/22/69 Retzler & Knight BR1,382,134 1/29/75 Frederick W. Lewis 1,405,851 2/7/22 Hultman 1,554,095 9/15/25 Zimmerman 2,776,521 1/8/57 Grutta 2,972,833 2/28/61 Christiansen 3,005,282 10/24/61 Christiansen 3,162,973 12/29/64 Christiansen 3,242,610 3/29/66 Sloop, et al. 3,496,670 2/24/70 Heubl 3,603,025 9/7/71 Zimmerman 3,604,145 9/14/71 Crawley 3,894,354 7/15/75 Fabre 3,895,456 7/22/75 Hake 4,090,322 5/23/78 Harvey 4,055,019 10/25/77 Kristiansen 4,185,410 1/29/80 Knudsen 4,214,403 7/29/80 Mayr 4,253,268 3/3/81 Lyman 4,606,732 8/19/86 Lyman 4,764,144 8/16/88 Lyman 4,789,369 12/6/88 ______________________________________